In today's automotive engine systems, there is an increased demand for low cost, direct injection. In common rail injection systems, the fuel is delivered by means of a high pressure pump from a fuel tank to a fuel rail which serves as a storage reservoir for the fuel. The fuel is under high pressure in the fuel rail and can be injected directly into the cylinders via injection valves connected to the rail.
Current direct injection high pressure pump valves are calibrated based on tolerances which can be inaccurate. In addition, with the conventional valve construction, if a faulty valve is discovered during manufacturing, the entire valve may need to be reworked or scrapped.